Cocaine remains a major public health concern due to continuing increases in the number of emergency room admissions following cocaine use. Cardiovascular complications represent a large proportion of these admissions. Cardiovascular effects of cocaine are being extensively studied using various species of animals as model systems. Recent research has focused on determining whether proposed treatment agents will alter the cardiovascular effects of cocaine in conscious squirrel monkeys. Although not planned, it is likely that some individuals will use a treatment agent in combination with cocaine. Therefore, it is important to know whether these treatment agents may increase the cardiovascular risks associated with cocaine use. Squirrel monkeys are seated in standard restraint chairs and placed in sound attenuating chambers 5 days per week. Twice per week the monkeys are administered cocaine, a treatment agent, or the two in combination about 30 min into the session. Cardiovascular parameters are monitored for an additional 60 min. In conscious squirrel monkeys cocaine produces clear increases in BP and HR. Drugs that interact with dopamine have been tested for cardiovascular effects both alone and in combination with cocaine. Deprenyl is a selective MAO-B inhibitor. Deprenyl by itself produced only minimal changes in BP and HR and when given in combination with cocaine, the effects of cocaine were either unaltered or slightly reduced. GBR 12909, a selective dopamine uptake inhibitor, produced small increases in blood pressure and heart rate, but when given in combination with cocaine, no potentiation of the cocaine effect was observed. Similarly, the dopamine D1 agonist SKF 82958 produces increases in blood pressure and heart rate, but did not potentiate cocaines effects at the doses tested. In contrast, the dopamine autoreceptor agonist UH 232 produces increases in blood pressure and heart, and when given in combination with cocaine additive effects are observed. No significant effects on ECG were observed for any of the drugs. Therefore, of the drugs tested thus far, only UH 232 would appear to represent a significant risk when used in combination with cocaine. - cocaine, cardiovascular, blood pressure, heart rate, ECG, squirrel monkey